/-- These tests are for the Perl >= 5.10 features that PCRE supports. --/

/\H\h\V\v/
    X X\x0a
 0: X X\x0a
    X\x09X\x0b
 0: X\x09X\x0b
    ** Failers
No match
    \xa0 X\x0a   
No match
    
/\H*\h+\V?\v{3,4}/ 
    \x09\x20\xa0X\x0a\x0b\x0c\x0d\x0a
 0: \x09 \xa0X\x0a\x0b\x0c\x0d
    \x09\x20\xa0\x0a\x0b\x0c\x0d\x0a
 0: \x09 \xa0\x0a\x0b\x0c\x0d
    \x09\x20\xa0\x0a\x0b\x0c
 0: \x09 \xa0\x0a\x0b\x0c
    ** Failers 
No match
    \x09\x20\xa0\x0a\x0b
No match
     
/\H{3,4}/
    XY  ABCDE
 0: ABCD
    XY  PQR ST 
 0: PQR
    
/.\h{3,4}./
    XY  AB    PQRS
 0: B    P

/\h*X\h?\H+Y\H?Z/
    >XNNNYZ
 0: XNNNYZ
    >  X NYQZ
 0:   X NYQZ
    ** Failers
No match
    >XYZ   
No match
    >  X NY Z
No match

/\v*X\v?Y\v+Z\V*\x0a\V+\x0b\V{2,3}\x0c/
    >XY\x0aZ\x0aA\x0bNN\x0c
 0: XY\x0aZ\x0aA\x0bNN\x0c
    >\x0a\x0dX\x0aY\x0a\x0bZZZ\x0aAAA\x0bNNN\x0c
 0: \x0a\x0dX\x0aY\x0a\x0bZZZ\x0aAAA\x0bNNN\x0c

/(foo)\Kbar/
    foobar
 0: bar
 1: foo
   
/(foo)(\Kbar|baz)/
    foobar
 0: bar
 1: foo
 2: bar
    foobaz 
 0: foobaz
 1: foo
 2: baz

/(foo\Kbar)baz/
    foobarbaz
 0: barbaz
 1: foobar

/abc\K|def\K/g+
    Xabcdefghi
 0: 
 0+ defghi
 0: 
 0+ ghi

/ab\Kc|de\Kf/g+
    Xabcdefghi
 0: c
 0+ defghi
 0: f
 0+ ghi
    
/(?=C)/g+
    ABCDECBA
 0: 
 0+ CDECBA
 0: 
 0+ CBA
    
/^abc\K/+
    abcdef
 0: 
 0+ def
    ** Failers
No match
    defabcxyz   
No match

/^(a(b))\1\g1\g{1}\g-1\g{-1}\g{-02}Z/
    ababababbbabZXXXX
 0: ababababbbabZ
 1: ab
 2: b

/(?<A>tom|bon)-\g{A}/
    tom-tom
 0: tom-tom
 1: tom
    bon-bon 
 0: bon-bon
 1: bon
    
/(^(a|b\g{-1}))/
    bacxxx
No match

/(?|(abc)|(xyz))\1/
    abcabc
 0: abcabc
 1: abc
    xyzxyz 
 0: xyzxyz
 1: xyz
    ** Failers
No match
    abcxyz
No match
    xyzabc   
No match
    
/(?|(abc)|(xyz))(?1)/
    abcabc
 0: abcabc
 1: abc
    xyzabc 
 0: xyzabc
 1: xyz
    ** Failers 
No match
    xyzxyz 
No match
 
/^X(?5)(a)(?|(b)|(q))(c)(d)(Y)/
    XYabcdY
 0: XYabcdY
 1: a
 2: b
 3: c
 4: d
 5: Y

/^X(?7)(a)(?|(b|(r)(s))|(q))(c)(d)(Y)/
    XYabcdY
 0: XYabcdY
 1: a
 2: b
 3: <unset>
 4: <unset>
 5: c
 6: d
 7: Y

/^X(?7)(a)(?|(b|(?|(r)|(t))(s))|(q))(c)(d)(Y)/
    XYabcdY
 0: XYabcdY
 1: a
 2: b
 3: <unset>
 4: <unset>
 5: c
 6: d
 7: Y

/(?'abc'\w+):\k<abc>{2}/
    a:aaxyz
 0: a:aa
 1: a
    ab:ababxyz
 0: ab:abab
 1: ab
    ** Failers
No match
    a:axyz
No match
    ab:abxyz
No match

/(?'abc'\w+):\g{abc}{2}/
    a:aaxyz
 0: a:aa
 1: a
    ab:ababxyz
 0: ab:abab
 1: ab
    ** Failers
No match
    a:axyz
No match
    ab:abxyz
No match

/^(?<ab>a)? (?(<ab>)b|c) (?('ab')d|e)/x
    abd
 0: abd
 1: a
    ce
 0: ce

/^(a.)\g-1Z/
    aXaXZ
 0: aXaXZ
 1: aX

/^(a.)\g{-1}Z/
    aXaXZ
 0: aXaXZ
 1: aX

/^(?(DEFINE) (?<A> a) (?<B> b) )  (?&A) (?&B) /x
    abcd
 0: ab

/(?<NAME>(?&NAME_PAT))\s+(?<ADDR>(?&ADDRESS_PAT))
  (?(DEFINE)
  (?<NAME_PAT>[a-z]+)
  (?<ADDRESS_PAT>\d+)
  )/x
    metcalfe 33
 0: metcalfe 33
 1: metcalfe
 2: 33

/(?(DEFINE)(?<byte>2[0-4]\d|25[0-5]|1\d\d|[1-9]?\d))\b(?&byte)(\.(?&byte)){3}/
    1.2.3.4
 0: 1.2.3.4
 1: <unset>
 2: .4
    131.111.10.206
 0: 131.111.10.206
 1: <unset>
 2: .206
    10.0.0.0
 0: 10.0.0.0
 1: <unset>
 2: .0
    ** Failers
No match
    10.6
No match
    455.3.4.5
No match

/\b(?&byte)(\.(?&byte)){3}(?(DEFINE)(?<byte>2[0-4]\d|25[0-5]|1\d\d|[1-9]?\d))/
    1.2.3.4
 0: 1.2.3.4
 1: .4
    131.111.10.206
 0: 131.111.10.206
 1: .206
    10.0.0.0
 0: 10.0.0.0
 1: .0
    ** Failers
No match
    10.6
No match
    455.3.4.5
No match

/^(\w++|\s++)*$/
    now is the time for all good men to come to the aid of the party
 0: now is the time for all good men to come to the aid of the party
 1: party
    *** Failers
No match
    this is not a line with only words and spaces!
No match

/(\d++)(\w)/
    12345a
 0: 12345a
 1: 12345
 2: a
    *** Failers
No match
    12345+
No match

/a++b/
    aaab
 0: aaab

/(a++b)/
    aaab
 0: aaab
 1: aaab

/(a++)b/
    aaab
 0: aaab
 1: aaa

/([^()]++|\([^()]*\))+/
    ((abc(ade)ufh()()x
 0: abc(ade)ufh()()x
 1: x

/\(([^()]++|\([^()]+\))+\)/
    (abc)
 0: (abc)
 1: abc
    (abc(def)xyz)
 0: (abc(def)xyz)
 1: xyz
    *** Failers
No match
    ((()aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
No match

/^([^()]|\((?1)*\))*$/
    abc
 0: abc
 1: c
    a(b)c
 0: a(b)c
 1: c
    a(b(c))d
 0: a(b(c))d
 1: d
    *** Failers)
No match
    a(b(c)d
No match

/^>abc>([^()]|\((?1)*\))*<xyz<$/
   >abc>123<xyz<
 0: >abc>123<xyz<
 1: 3
   >abc>1(2)3<xyz<
 0: >abc>1(2)3<xyz<
 1: 3
   >abc>(1(2)3)<xyz<
 0: >abc>(1(2)3)<xyz<
 1: (1(2)3)

/^(?:((.)(?1)\2|)|((.)(?3)\4|.))$/i
    1221
 0: 1221
 1: 1221
 2: 1
    Satanoscillatemymetallicsonatas
 0: Satanoscillatemymetallicsonatas
 1: <unset>
 2: <unset>
 3: Satanoscillatemymetallicsonatas
 4: S
    AmanaplanacanalPanama
 0: AmanaplanacanalPanama
 1: <unset>
 2: <unset>
 3: AmanaplanacanalPanama
 4: A
    AblewasIereIsawElba
 0: AblewasIereIsawElba
 1: <unset>
 2: <unset>
 3: AblewasIereIsawElba
 4: A
    *** Failers
No match
    Thequickbrownfox
No match

/^(\d+|\((?1)([+*-])(?1)\)|-(?1))$/
    12
 0: 12
 1: 12
    (((2+2)*-3)-7)
 0: (((2+2)*-3)-7)
 1: (((2+2)*-3)-7)
 2: -
    -12
 0: -12
 1: -12
    *** Failers
No match
    ((2+2)*-3)-7)
No match

/^(x(y|(?1){2})z)/
    xyz
 0: xyz
 1: xyz
 2: y
    xxyzxyzz
 0: xxyzxyzz
 1: xxyzxyzz
 2: xyzxyz
    *** Failers
No match
    xxyzz
No match
    xxyzxyzxyzz
No match

/((< (?: (?(R) \d++  | [^<>]*+) | (?2)) * >))/x
    <>
 0: <>
 1: <>
 2: <>
    <abcd>
 0: <abcd>
 1: <abcd>
 2: <abcd>
    <abc <123> hij>
 0: <abc <123> hij>
 1: <abc <123> hij>
 2: <abc <123> hij>
    <abc <def> hij>
 0: <def>
 1: <def>
 2: <def>
    <abc<>def>
 0: <abc<>def>
 1: <abc<>def>
 2: <abc<>def>
    <abc<>
 0: <>
 1: <>
 2: <>
    *** Failers
No match
    <abc
No match

/^a+(*FAIL)/
    aaaaaa
No match
    
/a+b?c+(*FAIL)/
    aaabccc
No match

/a+b?(*PRUNE)c+(*FAIL)/
    aaabccc
No match

/a+b?(*COMMIT)c+(*FAIL)/
    aaabccc
No match
    
/a+b?(*SKIP)c+(*FAIL)/
    aaabcccaaabccc
No match

/^(?:aaa(*THEN)\w{6}|bbb(*THEN)\w{5}|ccc(*THEN)\w{4}|\w{3})/
    aaaxxxxxx
 0: aaaxxxxxx
    aaa++++++ 
 0: aaa
    bbbxxxxx
 0: bbbxxxxx
    bbb+++++ 
 0: bbb
    cccxxxx
 0: cccxxxx
    ccc++++ 
 0: ccc
    dddddddd   
 0: ddd

/^(aaa(*THEN)\w{6}|bbb(*THEN)\w{5}|ccc(*THEN)\w{4}|\w{3})/
    aaaxxxxxx
 0: aaaxxxxxx
 1: aaaxxxxxx
    aaa++++++ 
 0: aaa
 1: aaa
    bbbxxxxx
 0: bbbxxxxx
 1: bbbxxxxx
    bbb+++++ 
 0: bbb
 1: bbb
    cccxxxx
 0: cccxxxx
 1: cccxxxx
    ccc++++ 
 0: ccc
 1: ccc
    dddddddd   
 0: ddd
 1: ddd

/a+b?(*THEN)c+(*FAIL)/
    aaabccc
No match

/(A (A|B(*ACCEPT)|C) D)(E)/x
    AB
 0: AB
 1: AB
 2: B
    ABX
 0: AB
 1: AB
 2: B
    AADE
 0: AADE
 1: AAD
 2: A
 3: E
    ACDE
 0: ACDE
 1: ACD
 2: C
 3: E
    ** Failers
No match
    AD 
No match
        
/^\W*+(?:((.)\W*+(?1)\W*+\2|)|((.)\W*+(?3)\W*+\4|\W*+.\W*+))\W*+$/i
    1221
 0: 1221
 1: 1221
 2: 1
    Satan, oscillate my metallic sonatas!
 0: Satan, oscillate my metallic sonatas!
 1: <unset>
 2: <unset>
 3: Satan, oscillate my metallic sonatas
 4: S
    A man, a plan, a canal: Panama!
 0: A man, a plan, a canal: Panama!
 1: <unset>
 2: <unset>
 3: A man, a plan, a canal: Panama
 4: A
    Able was I ere I saw Elba.
 0: Able was I ere I saw Elba.
 1: <unset>
 2: <unset>
 3: Able was I ere I saw Elba
 4: A
    *** Failers
No match
    The quick brown fox
No match

/^((.)(?1)\2|.)$/
    a
 0: a
 1: a
    aba
 0: aba
 1: aba
 2: a
    aabaa  
 0: aabaa
 1: aabaa
 2: a
    abcdcba 
 0: abcdcba
 1: abcdcba
 2: a
    pqaabaaqp  
 0: pqaabaaqp
 1: pqaabaaqp
 2: p
    ablewasiereisawelba
 0: ablewasiereisawelba
 1: ablewasiereisawelba
 2: a
    rhubarb
No match
    the quick brown fox  
No match

/(a)(?<=b(?1))/
    baz
 0: a
 1: a
    ** Failers
No match
    caz  
No match
    
/(?<=b(?1))(a)/
    zbaaz
 0: a
 1: a
    ** Failers
No match
    aaa  
No match
    
/(?<X>a)(?<=b(?&X))/
    baz
 0: a
 1: a

/^(?|(abc)|(def))\1/
    abcabc
 0: abcabc
 1: abc
    defdef 
 0: defdef
 1: def
    ** Failers
No match
    abcdef
No match
    defabc   
No match
    
/^(?|(abc)|(def))(?1)/
    abcabc
 0: abcabc
 1: abc
    defabc
 0: defabc
 1: def
    ** Failers
No match
    defdef
No match
    abcdef    
No match

/(?:a(?<quote> (?<apostrophe>')|(?<realquote>")) |b(?<quote> (?<apostrophe>')|(?<realquote>")) ) (?('quote')[a-z]+|[0-9]+)/xJ
    a\"aaaaa
 0: a"aaaaa
 1: "
 2: <unset>
 3: "
    b\"aaaaa 
 0: b"aaaaa
 1: <unset>
 2: <unset>
 3: <unset>
 4: "
 5: <unset>
 6: "
    ** Failers 
No match
    b\"11111
No match

/(?:(?1)|B)(A(*F)|C)/
    ABCD
 0: BC
 1: C
    CCD
 0: CC
 1: C
    ** Failers
No match
    CAD   
No match

/^(?:(?1)|B)(A(*F)|C)/
    CCD
 0: CC
 1: C
    BCD 
 0: BC
 1: C
    ** Failers
No match
    ABCD
No match
    CAD
No match
    BAD    
No match

/(?:(?1)|B)(A(*ACCEPT)XX|C)D/
    AAD
 0: AA
 1: A
    ACD
 0: ACD
 1: C
    BAD
 0: BA
 1: A
    BCD
 0: BCD
 1: C
    BAX  
 0: BA
 1: A
    ** Failers
No match
    ACX
No match
    ABC   
No match

/(?(DEFINE)(A))B(?1)C/
    BAC
 0: BAC

/(?(DEFINE)((A)\2))B(?1)C/
    BAAC
 0: BAAC

/(?<pn> \( ( [^()]++ | (?&pn) )* \) )/x
    (ab(cd)ef)
 0: (ab(cd)ef)
 1: (ab(cd)ef)
 2: ef

/^(?!a(*SKIP)b)/
    ac
 0: 
    
/^(?=a(*SKIP)b|ac)/
    ** Failers
No match
    ac
No match
    
/^(?=a(*THEN)b|ac)/
    ac
 0: 
    
/^(?=a(*PRUNE)b)/
    ab  
 0: 
    ** Failers 
No match
    ac
No match

/^(?=a(*ACCEPT)b)/
    ac
 0: 

/^(?(?!a(*SKIP)b))/
    ac
 0: 

/(?>a\Kb)/
    ab
 0: b

/((?>a\Kb))/
    ab
 0: b
 1: ab

/(a\Kb)/
    ab
 0: b
 1: ab
    
/^a\Kcz|ac/
    ac
 0: ac
    
/(?>a\Kbz|ab)/
    ab 
 0: ab

/^(?&t)(?(DEFINE)(?<t>a\Kb))$/
    ab
 0: b

/^([^()]|\((?1)*\))*$/
    a(b)c
 0: a(b)c
 1: c
    a(b(c)d)e 
 0: a(b(c)d)e
 1: e

/(?P<L1>(?P<L2>0)(?P>L1)|(?P>L2))/
    0
 0: 0
 1: 0
    00
 0: 00
 1: 00
 2: 0
    0000  
 0: 0000
 1: 0000
 2: 0

/(?P<L1>(?P<L2>0)|(?P>L2)(?P>L1))/
    0
 0: 0
 1: 0
 2: 0
    00
 0: 0
 1: 0
 2: 0
    0000  
 0: 0
 1: 0
 2: 0

/--- This one does fail, as expected, in Perl. It needs the complex item at the
     end of the pattern. A single letter instead of (B|D) makes it not fail,
     which I think is a Perl bug. --- /

/A(*COMMIT)(B|D)/
    ACABX
No match

/--- Check the use of names for failure ---/

/^(A(*PRUNE:A)B|C(*PRUNE:B)D)/K
    ** Failers
No match
    AC
No match, mark = A
    CB    
No match, mark = B
    
/--- Force no study, otherwise mark is not seen. The studied version is in
     test 2 because it isn't Perl-compatible. ---/

/(*MARK:A)(*SKIP:B)(C|X)/KSS
    C
 0: C
 1: C
MK: A
    D
No match, mark = A
     
/^(A(*THEN:A)B|C(*THEN:B)D)/K
    ** Failers
No match
    CB    
No match, mark = B

/^(?:A(*THEN:A)B|C(*THEN:B)D)/K
    CB    
No match, mark = B
    
/^(?>A(*THEN:A)B|C(*THEN:B)D)/K
    CB    
No match, mark = B
    
/--- This should succeed, as the skip causes bump to offset 1 (the mark). Note
that we have to have something complicated such as (B|Z) at the end because,
for Perl, a simple character somehow causes an unwanted optimization to mess
with the handling of backtracking verbs. ---/

/A(*MARK:A)A+(*SKIP:A)(B|Z) | AC/xK
    AAAC
 0: AC
    
/--- Test skipping over a non-matching mark. ---/

/A(*MARK:A)A+(*MARK:B)(*SKIP:A)(B|Z) | AC/xK
    AAAC
 0: AC
    
/--- Check shorthand for MARK ---/

/A(*:A)A+(*SKIP:A)(B|Z) | AC/xK
    AAAC
 0: AC

/--- Don't loop! Force no study, otherwise mark is not seen. ---/

/(*:A)A+(*SKIP:A)(B|Z)/KSS
    AAAC
No match, mark = A

/--- This should succeed, as a non-existent skip name disables the skip ---/ 

/A(*MARK:A)A+(*SKIP:B)(B|Z) | AC/xK
    AAAC
 0: AC

/A(*MARK:A)A+(*SKIP:B)(B|Z) | AC(*:B)/xK
    AAAC
 0: AC
MK: B

/--- We use something more complicated than individual letters here, because
that causes different behaviour in Perl. Perhaps it disables some optimization;
anyway, the result now matches PCRE in that no tag is passed back for the 
failures. ---/
    
/(A|P)(*:A)(B|P) | (X|P)(X|P)(*:B)(Y|P)/xK
    AABC
 0: AB
 1: A
 2: B
MK: A
    XXYZ 
 0: XXY
 1: <unset>
 2: <unset>
 3: X
 4: X
 5: Y
MK: B
    ** Failers
No match
    XAQQ  
No match
    XAQQXZZ  
No match
    AXQQQ 
No match
    AXXQQQ 
No match
    
/--- COMMIT at the start of a pattern should act like an anchor. Again, 
however, we need the complication for Perl. ---/

/(*COMMIT)(A|P)(B|P)(C|P)/
    ABCDEFG
 0: ABC
 1: A
 2: B
 3: C
    ** Failers
No match
    DEFGABC  
No match

/--- COMMIT inside an atomic group can't stop backtracking over the group. ---/

/(\w+)(?>b(*COMMIT))\w{2}/
    abbb
 0: abbb
 1: a

/(\w+)b(*COMMIT)\w{2}/
    abbb
No match

/--- Check opening parens in comment when seeking forward reference. ---/ 

/(?&t)(?#()(?(DEFINE)(?<t>a))/
    bac
 0: a

/--- COMMIT should override THEN ---/

/(?>(*COMMIT)(?>yes|no)(*THEN)(*F))?/
  yes
No match

/(?>(*COMMIT)(yes|no)(*THEN)(*F))?/
  yes
No match

/b?(*SKIP)c/
    bc
 0: bc
    abc
 0: bc
   
/(*SKIP)bc/
    a
No match

/(*SKIP)b/
    a 
No match

/(?P<abn>(?P=abn)xxx|)+/
    xxx
 0: 
 1: 

/(?i:([^b]))(?1)/
    aa
 0: aa
 1: a
    aA     
 0: aA
 1: a
    ** Failers
 0: **
 1: *
    ab
No match
    aB
No match
    Ba
No match
    ba
No match

/^(?&t)*+(?(DEFINE)(?<t>a))\w$/
    aaaaaaX
 0: aaaaaaX
    ** Failers 
No match
    aaaaaa 
No match

/^(?&t)*(?(DEFINE)(?<t>a))\w$/
    aaaaaaX
 0: aaaaaaX
    aaaaaa 
 0: aaaaaa

/^(a)*+(\w)/
    aaaaX
 0: aaaaX
 1: a
 2: X
    YZ 
 0: Y
 1: <unset>
 2: Y
    ** Failers 
No match
    aaaa
No match

/^(?:a)*+(\w)/
    aaaaX
 0: aaaaX
 1: X
    YZ 
 0: Y
 1: Y
    ** Failers 
No match
    aaaa
No match

/^(a)++(\w)/
    aaaaX
 0: aaaaX
 1: a
 2: X
    ** Failers 
No match
    aaaa
No match
    YZ 
No match

/^(?:a)++(\w)/
    aaaaX
 0: aaaaX
 1: X
    ** Failers 
No match
    aaaa
No match
    YZ 
No match

/^(a)?+(\w)/
    aaaaX
 0: aa
 1: a
 2: a
    YZ 
 0: Y
 1: <unset>
 2: Y

/^(?:a)?+(\w)/
    aaaaX
 0: aa
 1: a
    YZ 
 0: Y
 1: Y

/^(a){2,}+(\w)/
    aaaaX
 0: aaaaX
 1: a
 2: X
    ** Failers
No match
    aaa
No match
    YZ 
No match

/^(?:a){2,}+(\w)/
    aaaaX
 0: aaaaX
 1: X
    ** Failers
No match
    aaa
No match
    YZ 
No match

/(a|)*(?1)b/
    b
 0: b
 1: 
    ab
 0: ab
 1: 
    aab  
 0: aab
 1: 

/(a)++(?1)b/
    ** Failers
No match
    ab 
No match
    aab
No match

/(a)*+(?1)b/
    ** Failers
No match
    ab
No match
    aab  
No match

/(?1)(?:(b)){0}/
    b
 0: b

/(foo ( \( ((?:(?> [^()]+ )|(?2))*) \) ) )/x
    foo(bar(baz)+baz(bop))
 0: foo(bar(baz)+baz(bop))
 1: foo(bar(baz)+baz(bop))
 2: (bar(baz)+baz(bop))
 3: bar(baz)+baz(bop)

/(A (A|B(*ACCEPT)|C) D)(E)/x
    AB
 0: AB
 1: AB
 2: B

/\A.*?(?:a|b(*THEN)c)/
    ba
 0: ba

/\A.*?(?:a|bc)/
    ba
 0: ba

/\A.*?(a|b(*THEN)c)/
    ba
 0: ba
 1: a

/\A.*?(a|bc)/
    ba
 0: ba
 1: a

/\A.*?(?:a|b(*THEN)c)++/
    ba
 0: ba

/\A.*?(?:a|bc)++/
    ba
 0: ba

/\A.*?(a|b(*THEN)c)++/
    ba
 0: ba
 1: a

/\A.*?(a|bc)++/
    ba
 0: ba
 1: a

/\A.*?(?:a|b(*THEN)c|d)/
    ba
 0: ba

/\A.*?(?:a|bc|d)/
    ba
 0: ba

/(?:(b))++/
    beetle
 0: b
 1: b

/(?(?=(a(*ACCEPT)z))a)/
    a
 0: a
 1: a

/^(a)(?1)+ab/
    aaaab
 0: aaaab
 1: a
    
/^(a)(?1)++ab/
    aaaab
No match

/^(?=a(*:M))aZ/K
    aZbc
 0: aZ
MK: M

/^(?!(*:M)b)aZ/K
    aZbc
 0: aZ

/(?(DEFINE)(a))?b(?1)/
    backgammon
 0: ba

/^\N+/
    abc\ndef
 0: abc
    
/^\N{1,}/
    abc\ndef 
 0: abc

/(?(R)a+|(?R)b)/
    aaaabcde
 0: aaaab

/(?(R)a+|((?R))b)/
    aaaabcde
 0: aaaab
 1: aaaa

/((?(R)a+|(?1)b))/
    aaaabcde
 0: aaaab
 1: aaaab

/((?(R1)a+|(?1)b))/
    aaaabcde
 0: aaaab
 1: aaaab

/a(*:any 
name)/K
    abc
 0: a
MK: any 
name
    
/(?>(?&t)c|(?&t))(?(DEFINE)(?<t>a|b(*PRUNE)c))/
    a
 0: a
    ba
 0: a
    bba 
 0: a
    
/--- Checking revised (*THEN) handling ---/ 

/--- Capture ---/

/^.*? (a(*THEN)b) c/x
    aabc
No match

/^.*? (a(*THEN)b|(*F)) c/x
    aabc
 0: aabc
 1: ab

/^.*? ( (a(*THEN)b) | (*F) ) c/x
    aabc
 0: aabc
 1: ab
 2: ab

/^.*? ( (a(*THEN)b) ) c/x
    aabc
No match

/--- Non-capture ---/

/^.*? (?:a(*THEN)b) c/x
    aabc
No match

/^.*? (?:a(*THEN)b|(*F)) c/x
    aabc
 0: aabc

/^.*? (?: (?:a(*THEN)b) | (*F) ) c/x
    aabc
 0: aabc

/^.*? (?: (?:a(*THEN)b) ) c/x
    aabc
No match

/--- Atomic ---/

/^.*? (?>a(*THEN)b) c/x
    aabc
No match

/^.*? (?>a(*THEN)b|(*F)) c/x
    aabc
 0: aabc

/^.*? (?> (?>a(*THEN)b) | (*F) ) c/x
    aabc
 0: aabc

/^.*? (?> (?>a(*THEN)b) ) c/x
    aabc
No match

/--- Possessive capture ---/

/^.*? (a(*THEN)b)++ c/x
    aabc
No match

/^.*? (a(*THEN)b|(*F))++ c/x
    aabc
 0: aabc
 1: ab

/^.*? ( (a(*THEN)b)++ | (*F) )++ c/x
    aabc
 0: aabc
 1: ab
 2: ab

/^.*? ( (a(*THEN)b)++ )++ c/x
    aabc
No match

/--- Possessive non-capture ---/

/^.*? (?:a(*THEN)b)++ c/x
    aabc
No match

/^.*? (?:a(*THEN)b|(*F))++ c/x
    aabc
 0: aabc

/^.*? (?: (?:a(*THEN)b)++ | (*F) )++ c/x
    aabc
 0: aabc

/^.*? (?: (?:a(*THEN)b)++ )++ c/x
    aabc
No match
    
/--- Condition assertion ---/

/^(?(?=a(*THEN)b)ab|ac)/
    ac
 0: ac
 
/--- Condition ---/

/^.*?(?(?=a)a|b(*THEN)c)/
    ba
No match

/^.*?(?:(?(?=a)a|b(*THEN)c)|d)/
    ba
 0: ba

/^.*?(?(?=a)a(*THEN)b|c)/
    ac
No match

/--- Assertion ---/

/^.*(?=a(*THEN)b)/ 
    aabc
 0: a

/------------------------------/

/-- End of testinput11 --/
